In modern "enterprise" computing environments, that is, computer systems for use in an office environment in a company, a number of personal computers, workstations, mini-computers and mainframe computers, along with other devices such as large mass storage subsystems, network printers and interfaces to the public telephony system, may be interconnected to provide an integrated environment in which information may be shared among users in the company. Typically, users may be performing a variety of operations, including order receipt, manufacturing, shipping, billing, inventory control, and other operations, in which sharing of data on a real-time basis may provide a significant advantage over, for example, maintaining separate records and attempting to later reconcile them. The users may operate on their own data, which they may maintain on the computers they are using, or alternatively they may share data through the large mass storage subsystems.
One such large mass storage subsystem is described in, for example, U.S. Pat. No. 5,206,939, entitled System And Method For Disk Mapping And Data Retrieval, issued Apr. 27, 1993 to Moshe Yanai, et al (hereinafter, "the '939 patent"), U.S. patent application Ser. No. 07/893,509 filed Jun. 4, 1995, in the name of Moshe Yanai, et al., entitled "System And Method For Dynamically Controlling Cache Management" (hereinafter referred to as "the Yanai patent application"), and U.S. Pat. No. 5,592,432, entitled "Cache Management System Using Time Stamping For Replacement Queue," issued Jan. 7, 1997 in the name of Natan Vishlitzky, et al., all of which are assigned to the assignee of the present invention and incorporated herein by reference. That patent and those applications generally describe an arrangement which allows data, as used by computers, organized in records, with each record being in well-known "CKD" ("count-key-data") format, to be stored in disk storage devices which provide a "fixed block" storage architecture. In this arrangement, a large cache is used to buffer data that is transferred from the storage devices for use by the respective computers, and, if the data has been modified, transferred back from to the storage devices for storage.